The present invention pertains to a vascular catheter assembly for penetration through tissue and for cardiac stimulation, and methods thereof. More particularly, the present invention pertains to a tubular member containing a stylet and insertable into a cardiac chamber for blunt boring of an opening through the endocardial, myocardial and epicardial tissue for passage of the tubular member and stylet into the pericardial space. Either the boring stylet itself, or a different stylet can be passed through this opening to provide cardiac stimulation.
The pericardium of the heart includes the pericardial sac, a tough, fibrous membrane surrounding the heart; the pericardial space, a void filled with serous fluid; and the epicardial layer, the exterior surface of the heart. In addition to the pericardium, the heart has the myocardium, a middle, muscular layer; and the endocardium, an inner layer on the walls of the heart's atrial and ventricular chambers.
In order to gain access to the epicardial surface of the heart, for ablation of arrhythmic areas, implantation of defibrillation electrodes or mapping of the epicardial surface, for example, a thoractomy is often required.
In addition to the time, expense, operating and infection risks, and patient discomfort associated with opening the patient's thorax, another problem exists in gaining access to the epicardium by breaching the pericardial sac. Opening the pericardial sac allows the serous fluid to escape and blood to enter the pericardial space inviting additional cardiac complications such as infection and irritation.
A need thus exists for a catheter-based apparatus and method for vascular entry into the body, and particularly into the heart, that circumvents major thoracic surgery and minimizes the amount of organ bleeding that occurs when the stylet passes through organ tissue layers.